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Provisional Patent Applications


A potential client came to me with her provisional patent application. She had written it herself and then filed it via another patent agent. The document was a pleasant read and I understood her invention well. However, the provisional filing could have been improved.

For one thing, it should have had a claim in it. US patent law defines a patent application as having certain elements, one of which is at least one claim. However, many provisional patent applications don’t have any. Does it matter? Well, since the provisional patent application never gets examined, many argue that it doesn’t need the claim. This is only partially correct.

Many inventors plan to also file their full patent application “abroad” (in any other country other than the US). According to the Paris Convention (the basis for such foreign filings), the second patent application receives “priority” from the first patent application if the second patent application is filed within 12 months of the filing date of the first patent application. Note that the language is “patent application”. The first document must be a “patent application”. If the provisional patent application does not include a claim, then there is a question as to whether it can serve as a priority document.

If the purpose of filing the provisional patent application is simply to serve as a “disclosure document” (i.e. to prove that you came up with the invention by a certain date), then including a claim in the provisional patent application is less necessary. Nonetheless, I would still include a claim - it takes very little time to write a simple claim and you may be glad to have it later.

Something else that my new client neglected to do was to file an assignment transferring rights in the invention to her company. Most people don’t bother. After all, they argue, the provisional will not become a patent, it is not examined, and the real assignment to the company will be in the full application.

I disagree. Without the assignment, the individual inventors are the initial owners of the application. What happens when, during the 12 months until the full application is filed, one or more of the inventors has a falling out with the company? If the provisional patent application hasn’t been assigned to the company, it may be difficult to get the inventor who has left the company to later sign the assignment document. This happens surprisingly frequently. Better to file an assignment while the inventors are excited by their invention and still working at the company.

This also solves another problem. The company’s ownership of its IP is always checked in a due diligence process, whether prior to an investment by a venture capitalist or to a buyout by a large company. With the assignment already filed, the ownership question is easily answered.

Another potential pitfall is whether the provisional patent application has an “enabling” disclosure. Most inventors will write up their idea – what their product does and why it is wonderful. Most inventors, though, avoid telling the implementation details, either because they don’t have them or because of a mistaken belief that this will keep the patent application broader.

Unfortunately for them, a patent application has a requirement to provide an enabling disclosure – some explanation of how to implement the concepts that the inventor brought to the world. Without this, the provisional patent application is not valid. Often, inventors file their provisional patent application just before they publicize their invention. Since their publication of their ideas is a bar to filing a patent application in most countries, they need their previously filed provisional patent application to be valid. Otherwise, their later publication of their idea will act as prior art to their full patent application and their full patent application will not be patentable over their own prior art.

Provisional patent applications are popular since they are fast and inexpensive to file. But inventors need to keep strategic issues in mind, to ensure that the application gives real value.


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